This invention relates to apparatus for monitoring and controlling the operation of program-controlled systems. More particularly, it is concerned with apparatus for monitoring the power supply conditions and operating state of a program-controlled computer.
Computers are being used increasingly to control the operation of various types of equipment. If a computer is caused to be in an improper, or undefined, operating state, improper operation of the equipment occurs which may lead to damage to the equipment or to material being processed by the equipment. An undefined state of the computer may be due to incorrect initialization of the computer hardware upon start-up. Improper power supply levels during powering-up, powering-down, and low line voltage conditions can cause the computer to operate in an undefined state. Problems may also occur because of failure in the computer hardware or because of other electrical noise or transients.
Presently known computer systems provide some protective features. For example, computer systems typically include hardware for generating a reset signal after application of power in order to insure proper initialization.